Low energy laser therapy (LLLT) is used in the treatment of a broad range of conditions. LLLT improves wound healing, reduces edema, and relieves pain of various etiologies, including the treatment and repair of injured muscles and tendons. LLLT is also used during liposuction procedures to facilitate removal of fat by causing intracellular fat to be released into the interstice and post-operatively to reduce inflammation and pain.
LLLT utilizes low level laser energy, that is, the treatment has a dose rate that causes no immediate detectable temperature rise of the treated tissue and no macroscopically visible changes in tissue structure. Consequently, the treated and surrounding tissue is not heated and is not damaged. There are a number of variables in laser therapy including the wavelength of the laser beam, the area impinged by the laser beam, laser energy, pulse width, treatment duration and tissue characteristics. The success of each therapy depends on the relationship and combination of these variables. For example, liposuction may be facilitated with one regimen utilizing a given wavelength and treatment duration, whereas pain may be treated with a regimen utilizing a different wavelength and treatment duration, and inflammation a third regimen.
Laser therapy has also been used as a depilatory to stop hair growth or to eliminate unwanted hair. These devices use relatively high-level laser energy, however, to thermally destroy offending hair follicles. U.S. Pat. No. 5,630,811 issued to Miller describes the evolution of lasers used to remove unwanted hair.
In contrast to the previously-accepted belief that lasers could be used only for hair removal because of the destructive result of the high-level laser energy, LLLT has been recognized recently as a method for hair restoration. One device designed to exploit the biostimulation effects of low level laser therapy to promote hair restoration is described in International Published Patent Application number WO02098509 assigned to Inca Asset Management S.A. of Geneva, Switzerland. This patent application describes a canopy or helmet, similar to the helmets used as hair dyers in hair dressing salons. The device is supported on a stand and positioned over the head of a patient. A helmet-like arrangement is placed inside the canopy so that it can rotate back and forth through about a quarter of a turn.
The invention requires alternate periods of laser stimulation and rest. This is achieved by forming several band shaped formations of laser diodes arranged in two lines on the inside of the helmet. As the helmet is oscillated the illumination from the laser diodes is swept across the scalp of the patient. The two lines are offset so that the scalp is fully illuminated as the helmet is rotated. A control panel on the front of the canopy is used to control the rotation of the helmet and the activation of the laser diodes. An alternate embodiment is described in which a large number of diodes are located on the inside of the helmet so that the entire scalp is illuminated without the need for a rotating canopy. The activation of the laser diodes is controlled to achieve the alternating periods of stimulation and rest required by the invention. A major drawback of this invention is the mechanical requirements to achieve a rotating helmet. Another drawback is the cost of using a large number of laser diodes.
Other methods of hair restoration are known, including hair follicle stimulation by light-emitting diode (LED), massage, and application of hormone-stimulating medicaments. For example, U.S. Pat. No. 6,666,878 issued to Carlgren discloses a helmet having rows of LEDs which create a band of light that moves repeatedly over the area of scalp to be treated. In addition to the discomfort of wearing a helmet repeatedly for extended periods, this device suffers the disadvantage of requiring many LED's to treat the scalp and limiting treatment areas to specific geometries, which can result in uneven hair growth.
Another device, described in U.S. Pat. No. 6,497,719 issued to Pearl et al., uses a laser in combination with a comb. The furrows create an unobstructed path for the laser beam to reach the scalp of the user. However, because each treatment is relatively long and many treatments are required, it is difficult to use a hand-held laser. The user's arm gets tired holding the laser for the required amount of time. This limits the precision and duration of the treatment.
Another hand-held laser is described in the inventor's U.S. Pat. No. 6,013,096. This patent describes a hand-held housing that houses a red semiconductor laser and optics to deliver the beam from the laser to the skin of a patient. A simple timing circuit is provided for controlling the length of time a laser beam is emitted from the housing. An optical arrangement causes the emitted light to form a line on the patient's skin, the shape of the light as it impinges the patient's skin.
Reference may also be had to U.S. Pat. No. 6,746,473 which describes a device that delivers two or more laser beams with different characteristics to treat a patient for multiple types of problems during a single treatment. The patent application describes a hand-held housing that houses a plurality of laser energy sources and optics to direct laser beams from the sources to a patient. Control electronics are provided to vary such parameters as the pulse repetition rate. Optics are also provided to select the beam shape of the laser output, which in turn determines the beam spot.
Both of these devices rely on a static optical arrangement to produce a beam spot. Neither of the devices provides a means for varying the shape or size of the beam spot on demand, nor for automatically varying the resultant intensity. It has become clear in LLLT that there is benefit in being able to customize the delivery of the laser light treatment by changing the shape and energy distribution of the delivered beam spot. It has recently been discovered that overlapping areas of treatment can increase the effects of the therapy. Furthermore, both of these devices are hand-held, requiring a therapist to personally apply the laser therapy. This has the disadvantage of requiring the therapist to continuously attend the patient, as well as limiting the precision and duration of the treatment. It would be desirable to provide a device that can provide accurate and precise treatment to the patient without continuous human intervention.
Therefore, an object of this invention is to provide a laser therapy device that enables shaping of the delivered laser beam to suit multiple types of treatments and treatment patterns, including overlapping scan patterns. It is another object to provide a device that does not have to be held by the user during treatment. Another object is to provide a hair restoration device that does not require the use of a helmet and that provides accurate and precise treatment to the patient without continuous human intervention.